TET2, DNMT3A, IDH1, and JAK2 Mutation in Myeloproliferative Neoplasms in southern Iran

BACKGROUND

Five epigenetic regulator mutations are considered in myeloproliferative neoplasms (MPN) that have prognostic and therapeutic values.

OBJECTIVE

We aimed to evaluate these mutations in MPNs among the Iranian population.

METHODS

We selected 5 mutations in 4 epigenetic regulatory genes [TET2, DNMT3A, IDH1 (rs147001633&rs121913499), and JAK2)] and evaluated 130 patients with MPNs including 78 Philadelphia chromosome negative (49 ETs, 20 PVs, and 9 PMFs) and 52 Philadelphia chromosome-positive patients as well as 51 healthy controls.

RESULTS

Eight patients (6.5%) carried the DNMT3A mutation, 35 (27%) were positive for TET2 mutation and 64 (49.3%) had the JAK2V617F mutation. In the healthy controls, 16 (31.4%) cases had the TET2 mutation (15 Heterozygote + 1 Homozygote) and one had heterozygote JAK2 mutation. There was no statistically significant difference between patient groups for any of these mutations, except for JAK2. The JAK2 mutation rate was 18 (90%), 25 (51%), 7 (77.8%), 14 (26.9%) in polycythemia vera, essential thrombocythemia, primary myelofibrosis, and chronic myelocytic leukemia, respectively. Patients aged 60 and older were more likely to carry the TET2 mutation (23% vs. 39% in younger and older than 60 years old individuals, p=0.025). IDH1 was not detected at all and PV had the highest TET2 mutation 7(35%). Two PMF patients had a history of bone marrow transplantation that were negative for IDH1and DNMT3A and one was positive for TET2 mutation.

CONCLUSION

In the normal Iranian population, the heterozygote form of TET2 mutation is significant, especially in the elderly. No association was found between JAK2 and TET2 mutations. Both of them are more prevalent in the age group of 60 years and older. DNMT3A mutation has a low prevalence and occurs in both positive and negative MPNs.

Conversion of epoxides into 1,3-dioxolanes catalysed by high oxidation state metalloporphyrins

Tin(IV) tetraphenylporphyrin perchlorate, Sn(IV)(tpp)(ClO4)2, catalyses the efficient reaction of epoxides with acetone to give the corresponding 1,3-dioxolanes in good yields.

Preparation of an insoluble polymer-supported Mn (III) porphyrin and its use as a new alkene epoxidation and alkane hydroxylation catalyst

An easy and effective method to prepare a new supported Mn(III)-porphyrin by immobilisation of Mn(III)-5,10,15, 20-Tetrakis(p-sulfonatophenyl)porphyrin, [Mn(TPPS)], on poly(4-styrylmethyl)pyridinium chloride (PSMP) is reported. This catalyst was found to be efficient for catalysing alkene epoxidation and alkane hydroxylation with sodium periodate. This new heterogenised metalloporphyrin catalyst is of high stability and reusability.

Does short-term exposure to elevated levels of natural gamma radiation in Ramsar cause oxidative stress?

BACKGROUND

Ramsar, a city in northern Iran, has areas with some of the highest recorded levels of natural radiation among inhabited areas measured on the earth.

AIMS

To determine whether short-term exposure to extremely high levels of natural radiation induce oxidative stress.

MATERIALS AND METHODS

In this study, 53 Wistar rats were randomly divided into five groups of 10-12 animals. Animals in the 1(st) group were kept for 7 days in an outdoor area with normal background radiation while the 2(nd) , 3(rd) , 4(th) and 5(th) groups were kept in four different outdoor areas with naturally elevated levels of gamma radiation in Ramsar. A calibrated RDS-110 survey meter, mounted on a tripod approximately 1 m above the ground, was used to measure exposure rate at each location. On days 7 and 9 blood sampling was performed to assess the serum levels of catalase (CAT) and malondialdehyde (MDA). On day 8, all animals were exposed to a lethal dose of 8 Gy gamma radiations emitted by a Theratron Phoenix (Theratronics, Canada) Cobalt-60 (55 cGy/min) at Radiotherapy Department of Razi Hospital in Rasht, Iran.

RESULTS

Findings obtained in this study indicate that high levels of natural radiation cannot induce oxidative stress. CAT and MDA levels in almost all groups were not significantly different (P = 0.69 and P = 0.05, respectively). After exposure to the lethal dose, CAT and MDA levels in all groups were not significantly different (P = 0.054 and P = 0.163, respectively).

CONCLUSIONS

These findings indicate that short-term exposure to extremely high levels of natural radiation (up to 196 times higher than the normal background) does not induce oxidative stress.

Polymeric cyanide azo compounds dipole moments and photo-physical properties in solvents media

A quantitative study of solvent environment effects on the photo-physical properties of a group of polymeric cyano azo benzene compounds was carried out at room temperature. Absorption and emission spectra of this group of azo matter with similar structure and different statistical weight of azo block have been studied in different solvents. The solvatochromic method was used to estimate the dipole moments in ground and excited states. The nature and degree of solvent-solute interactions were characterized using Kamlet-Abboud-Taft multi-parameter polarity scale.

Excited state electric dipole moment of nile blue and brilliant cresyl blue: a comparative study

A solvatochromic study on the photophysical properties of two cationic oxazine dyes (brilliant cresyl blue and nile blue) was carried out. The electronic absorption and emission spectra of the dyes were recorded in various organic solvents with different polarity. The ground and the excited state dipole moments of the dyes were estimated from solvatochromic shift method. The solvent dependent spectral shifts in absorption and fluorescence spectra were analyzed by the Katritzky and Kamlet-Taft multi-parameter scales. This work is characterized by detailed quantitative studies on the nature and extent of solvent-solute interactions.

Tautomeric behavior of some azoquinoline dyes in liquid and liquid crystalline media

The absorption spectra of three azoquinolin-8-ol derivatives (o-, m-, p-cyano hydroxy azoquinolin dyes) were investigated in liquid and liquid crystalline solutions as a function of the solvent polarity. The spectral data of the dyes were compared in both ordinary liquid solvents and liquid crystalline media. Analysis of the spectral data was used to determine the azo and hydrazone forms in both the environments. The spectral shifts were correlated by Kamlet-Taft and Katritzky multi-parameter polarity scales. For the azoquinoline dyes, the azo form is almost entirely dominated in polar anisotropic hosts. In contrast, the compounds remain dominantly in hydrazone form in some polar solvents such as DMF. The polarized absorption spectra of the compounds in the anisotropic media were measured and their degree of anisotropies was determined.

Solvatochromism effects on the dipole moments and photo-physical behavior of some azo sulfonamide dyes

Absorption and emission spectra of three azo sulfonamide dyes with various molecular structures have been studied in different solvents. The solute photo-physical behavior depends strongly on the solvent-solute interactions and solvent microenvironment. In order to understand the effect of intermolecular interactions on spectral behaviors of these dyes in different solvents and to conceive nature and extent of solvent-solute interactions the spectral variations were analyzed by the linear solvation energy relationships concept. In addition, by means of solvatochromic method the dipole moments of these dyes, in ground and excited states, were investigated.

A comparative study on the aggregate formation of two oxazine dyes in aqueous and aqueous urea solutions

The visible absorption spectra of two oxazine dyes, brilliant cresyl blue and nile blue, in aqueous and aqueous urea solutions (0.01-1 M) were studied as a function of the dye concentration. Due to structural similarity of the investigated dyes, their spectral features were compared. The dimerization behavior of the dyes in water with or without urea was analyzed in terms of monomer-dimer equilibrium. The nature and structure of the interacting pairs for these dyes were discussed using the exciton theory. The dimerization constant values of the dyes in aqueous and aqueous urea solutions were calculated. For both the dyes in aqueous urea solutions, a reduction in dimer formation was observed. The excitonic parameters were compared with those of oxazine-1, which is structurally similar to the investigated dyes.

Dimeric spectra analysis in Microsoft Excel: a comparative study

The purpose of this work is to introduce the reader to an Add-in implementation, Decom. This implementation provides the whole processing requirements for analysis of dimeric spectra. General linear and nonlinear decomposition algorithms were integrated as an Excel Add-in for easy installation and usage. In this work, the results of several samples investigations were compared to those obtained by Datan.

Estimation of ground- and excited-state dipole moments of oxazine 1 in liquid and liquid crystalline media

The absorption and fluorescence spectra of a laser dye, oxazine-1 (OX1), in liquid and liquid crystalline media were studied at room temperature. The solvatochromic method was used to determine the ground- and excited-state dipole moments by means of Lippert-Mataga, Bakshiev, Kawski-Chamma-Viallet polarity functions. The solvent polarity has no large and regular effect on the spectral behavior of OX1, and thus it might be considered as a poor solvatochromic indicator dye. In addition, applicability of solvatochromic method for this dye in anisotropic media was investigated. On the other hand, nature and degree of the solute-solvent interactions were characterized using correlation of multi-parameter solvent polarity scales. Due to the theoretical restrictions and the dye molecular structure, deviations from the solvatochromic correlation were observed.

Intramolecular and intermolecular hydrogen-bonding effects on the dipole moments and photophysical properties of some anthraquinone dyes

Absorption and fluorescence spectra of three anthraquinone dyes with various substituents and molecular size were studied in different solvents. The photo-physical behavior of a dissolved dye depends strongly on the solvent-solute interactions and solvent nature. The solvatochromic method was used to investigate dipole moments of these dyes in ground and excited states. The spectral variations were analyzed by means of linear solvation energy relationships concept proposed by Kamlet and Taft. The results conceive the nature and extend of, specific and non-specific, solvent-solute interactions.

Effect of anisotropic and isotropic solvent on the dipole moment of coumarin dyes

The ground state (μ(g)) and the excited state (μ(e)) dipole moments of two coumarin laser dyes, coumarin 440 and 460, were studied at room temperature in various solvents, viz., general solvents, alcohols and liquid crystals at 298 K. In this work, we report dipole moment of laser dyes in different anisotropic (liquid crystal) and isotropic environments for understanding the effects of environments on the molecular dipole moment and comparing them. Ground and excited state dipole moments of coumarin dyes were evaluated by means of solvatochromic shift method. It was observed that dipole moment values of excited states (μ(e)) were higher than the corresponding ground state values (μ(g)) in all media.

Anisotropic media effect on the dipole moment of some coumarin dyes

The ground state (μ(g)) and the excited state (μ(e)) dipole moments of two coumarin laser dyes, C500 and C503, were studied at room temperature in various solvents, viz., aprotic solvents, alcohols and liquid crystals at 298 K. We report dipole moment of laser dyes in different anisotropic (liquid crystals) and isotropic environments. The dipole moments values in different media help to investigate environment effects on the molecular dipole moment and provide a straightforward method for comparing their properties. Ground and excited state dipole moments of coumarin dyes were evaluated by means of solvatochromic shift method. It was observed that dipole moment values of excited states (μ(e)) were higher than corresponding ground state values (μ(g)), indicating a substantial redistribution of the π-electron densities in a more polar excited state for the dyes investigated.

Substituent and solvent effects on the photo-physical properties of some coumarin dyes

Absorption and fluorescence spectra of three coumarin dyes with various substituents and alkyl groups have been recorded in solvents in the range of 200-730 nm. The photo-physical behavior of dissolved dye depends on the nature of its environment, i.e. the solvatochromic behaviors of coumarin dyes and solvent/solute hydrogen bonding interactions can be analyzed by means of linear solvation energy relationships concept proposed by Kamlet and Taft. The intensity, shape, and maximum wavelength of the absorption and fluorescence band of these dyes in solution depend strongly on the solvent-solute interactions and solvent nature. Hydrogen bonding interactions (specific solute-solvent interactions) between these dye-solvent complex and dipolarity/polarizability (non-specific solute-solvent interactions) control reorientation of solvent molecules around the dye.

Effect of polyacrylamide hydrophilic gel composition on photo-physical behavior of Oxazine 750

Electronic absorption spectra of Oxazine 750 dye in aqueous solutions and in polyacrylamide hydrogel matrix with different structural composition were studied at room temperature. The transport and the solute-solute interactions of the ionic dye in aqueous solutions across the hydrophilic gels were investigated via exploring spectral properties of the dye-loaded hydrogel. The nature of the dye pair interactions in these media was discussed using the Kasha exciton theory. In addition, the monomer-dimer equilibrium of Oxazine 750 in hydrogels with different compositional percentage has been determined by means of UV-vis spectroscopy and least square fitting methods.

Solvent polarizability and anisotropy effects on the photophysical behavior of oxazine 1: an appropriate polarizability indicator dye

The spectroscopic features of a laser dye, oxazine 1 (OX1), were investigated in liquid and in liquid crystalline solutions as a function of the solvent polarity and polarizability. The nature of spectral shift was investigated by studying the absorption spectra of the dye in different solvents. The spectral shifts were correlated by the solvent polarity and polarizability. As a result, the solvent polarity has no large and regular effect on the spectral behavior of the dye, and thus it might be considered as a poor solvatochromic dye. In contrast, an excellent linear correlation was observed between the solvent polarizability and the spectral properties of the dye, and therefore, this dye might be considered as a good indicator for measuring the solvent polarizability. The absorption and fluorescence spectra of the dye were investigated in nematic solvents with high birefringence. In nematic solvents, anisotropy of polarizability has a major contribution to the shaping of the absorbance and emission spectra of OX1.

Effects of surfactants on the molecular aggregation of rhodamine dyes in aqueous solutions

The aggregative properties of rhodamine 6G (R6G) and rhodamine B (RB) in aqueous solutions of cationic and anionic surfactants were studied using the absorption and fluorescence spectroscopic methods. The dye-surfactant interactions in aqueous and surfactant solutions were also studied. The spectroscopic studies were extended in order to determine the effect of molecular structure of the surfactants on the aggregative behavior of the rhodamine dyes. The aggregate structures and the nature of the interacting pairs in these dyes were discussed using the exciton theory.

Electronic absorption spectra of cresyl violet acetate in anisotropic and isotropic solvents

The isotropic and anisotropic solvation characteristics of cresyl violet acetate (CVA) were investigated in isotropic liquid solutions and in polar nematic matrices as a function of the solvent type and concentration. The interaction of the ionic dye with the anisotropic surrounding and with that of the isotropic solvents was investigated and compared. The experimental result suggests that the nematic liquid crystalline solvents might create stronger solvation than the isotropic solvents. The spectral shifts were correlated by the solvent permittivity and Kamlet-Taft parameters. The polarized absorption spectra of cresyl violet acetate were measured between 400 and 800 nm and the dichroic ratio R and degree of anisotropy S of this dye in the liquid crystalline host determined.

Mn (Br8TPPS) Supported on Amberlite IRA-400 as a Robust and Efficient Catalyst for Alkene Epoxidation and Alkane Hydroxylation

Manganese (III) meso-tetrakis(p-sulfonatophenyl)-β-octabromoporphyrin supported on Amberlite IRA-400 [Mn(Br₈TPPS)-Ad-400] is a robust and efficient catalyst for epoxidation of alkenes and hydroxylation of alkanes with sodium periodate at room temperature.

Apolipoprotein B as the best predictor of coronary artery disease in Iranian normolipidemic patients

OBJECTIVES

A relatively high proportion of Iranian patients with coronary artery disease (CAD) have normal levels of traditional lipid risk factors and show early onset of CAD. In this study we examined the roles of apolipoprotein B (apoB), apolipoprotein AI (apoAI) and lipoprotein (a) [LP(a)] in predicting coronary heart disease in normolipidemic patients and those with premature CAD (age < or = 50).

DESIGN AND METHODS

Serum levels of apoB, apoAI, and LP(a) were determined in a total of 567 Iranian patients who were candidates for coronary angiography. A subgroup of 142 patients (93 males, 49 females) with normal levels of classical lipid risk factors, and a subgroup of patients (130 males, 71 females) with age below 50 years were separately assessed for coronary risk factors.

RESULTS

ApoB concentrations were significantly higher in patients with CAD (CAD+) relative to patients without CAD (CAD-) in the two subgroups. Multiple logistic regression after controlling for age and others risk factors showed apoB as the best determinant of CAD in the normolipidemic subgroup (OR, 4.3, p < 0.001) and in the men aged < or = 50 (OR, 5.7, p < 0.001). ApoB was the best predictor of CAD in a subgroup of very young patients (age < or = 40, n = 77, OR, 8.6, p < 0.009). There was a significant correlation between severity of atherosclerosis and serum apoB concentration in the normolipidemic subgroup (r = 0.22, p < 0.008).

CONCLUSIONS

Our data indicate that serum concentration of apoB is the best discriminating factor to predict the presence or absence of atherosclerosis in Iranian normolipidemic individuals and young patients undergoing coronary angiography.

Parenteral nutrition-induced hepatobiliary dysfunction in infants and prepubertal rabbits

We analyzed clinical, biochemical, and histo- logic parameters of ten infants with parenteral nutrition-induced hepatobiliary dysfunction. The data were compared with the results of a rabbit model. All infants were born prematurely with low birth weight. Their clinical diagnoses were necrotizing enterocolitis (6), gastroschisis (1), intrauterine volvulus (1), and lung hypoplasia (2). All required total (TPN) or partial parenteral nutrition for at least 8 weeks. All had repeated episodes of infections or sepsis. A rise in bilirubin and aminotransferase levels occurred after a minimum of 5 weeks; peak bilirubin levels ranged from 4 to 14 mg% and aminotransferases from 40 to 140 IU/l. One child later developed gallstones. Liver biopsies after 1 to 24 months showed fibrosis, bile-duct proliferation, cholestasis, and hydropic degeneration. All of the above-mentioned clinical factors have been accused of causing the observed biochemical and histologic changes. In our rabbit model we were able to produce almost identical symptoms by TPN alone: gallbladder distension, sludge, and stones developed after 1-4 weeks of TPN as well as uncharacteristic changes in aminotransferases and bilirubin after 4 weeks. Liver histology revealed severe hydropic degeneration of zone 3 as early as 1 week after beginning TPN. A rise of fibrosis and bile-duct proliferation after 1 to 4 weeks of infusion was statistically significant. Cholestasis, as was observed in the infants, could not be detected. In our model, all alterations observed could be attributed exclusively to TPN. We therefore assume that TPN was the true cause of the dysfunction. In a second experimental series infusions were reduced to 80% PN and free access to lab chow. These animals produced normal feces, indicating physiologic enteral stimulation. They developed the same degenerative and proliferative histologic changes, whereas gallbladder distension, sludge, and stones were not noted. We conclude that: (1) The TPN solution itself is responsible for the histologic changes in the liver, which is supported by the fact that hydropic degeneration of zone 3 is typical of a direct toxic effect; and (2) Complete enteral starvation with an absence of enteral stimulation causes disease of the lower biliary tract.

Inhibition of adenylyl cyclase by alpha chemokines IL-8 and GRO-alpha in Chinese hamster ovary cells expressing R1 and R2 receptors

Interleukin-8 (IL-8) and growth-related oncogene protein-alpha (GRO-alpha) belong to a family of alpha chemokines. The biologic effects of IL-8 are realized by binding to two seven-transmembrane receptors R1 and R2 and that of GRO-alpha by binding to receptor R2. Chinese hamster ovary (CHO) cells stably expressing R1 and R2 have been used to demonstrate that the ligand-dependent signaling by both receptors is via the inhibition of adenylyl cyclase. This inhibition is pertussis toxin sensitive and could be mediated by G(alpha)i2, which is present in CHO cells. GRO-alpha inhibits adenylyl cyclase exclusively in CHO-R2 cells, and IL-8 inhibits in both CHO-R1 and CHO-R2 cells. The cAMP status in cells is an easy, reliable, quantifiable signal that is amenable to high throughput screening for small molecule analogs.

Receptor recognition and specificity of interleukin-8 is determined by residues that cluster near a surface-accessible hydrophobic pocket

To determine the regions of interleukin-8 (IL-8) that allow high affinity and interleukin-8 receptor type 1 (IL8R1)-specific binding of chemokines, we produced chimeric proteins containing structural domains from IL-8, which binds to both IL8R1 and interleukin-8 receptor type 2 (IL8R2) with high affinity, and from GRO gamma, which does not bind to IL8R1 and binds to IL8R2 with reduced affinity. Receptor binding activity was tested by competition of 125I-IL-8 binding to recombinant IL8R1 and IL8R2 cell lines. Substitution into IL-8 of the GRO gamma sequences corresponding to either the amino-terminal loop (amino acids 1-18) or the first beta-sheet (amino acids 18-32) reduced binding to both IL8R1 and IL8R2. The third beta-sheet of IL-8 (amino acids 46-53) was required for binding to IL8R1 but not IL8R2. Exchanges of the second beta-sheet (amino acids 32-46) or the carboxyl-terminal alpha-helix (amino acids 53-72) had no significant effect. When IL-8 sequences were substituted into GRO gamma, a single domain containing the second beta-sheet of IL-8 (amino acids 18-32) was sufficient to confer high affinity binding for both IL8R1 and IL8R2. The amino-terminal loop (amino acids 1-18) and the third beta-sheet (amino acids 46-53) of IL-8 had little effect when substituted individually but showed increased binding to both receptors when substituted in combination. Individual amino acid substitutions were made at positions where IL-8 and GRO gamma sequences differ within the regions of residues 11-21 and 46-53. IL-8 mutations L49A or L49F selectively inhibited binding to IL8R1. Mutations Y13L and F21N enhanced binding to IL8R1 with little effect on IL8R2. A combined mutation Y13L/S14Q selectively decreased binding to IL8R2. Residues Tyr13, Ser14, Phe21, and Lys49 are clustered in and around a surface-accessible hydrophobic pocket on IL-8 that is physically distant from the previously identified ELR binding sequence. A homology model of GRO gamma, constructed from the known structure of IL-8 by refinement calculations, indicated that access to the hydrophobic pocket was effectively abolished in GRO gamma. These studies suggest that the surface hydrophobic pocket and/or adjacent residues participate in IL-8 receptor recognition for both IL8R1 and IL8R2 and that the hydrophobic pocket itself may be essential for IL8R1 binding. Thus this region contains a second site for IL-8 receptor recognition that, in combination with the Glu4-Leu5-Arg6 region, can modulate receptor binding affinity and IL8R1 specificity.

Physical mapping of origins of replication in the fission yeast Schizosaccharomyces pombe

We isolated four fragments from the Schizosaccharomyces pombe genome that mediate autonomous replication. A two-dimensional gel analysis revealed that in each case initiation could be mapped to within the S. pombe sequences. In three of the fragments, initiation could be mapped to one discrete location. In the fourth fragment, subcloning and two-dimensional gel analysis suggested that two discrete origins of replication were located within 3 kb of each other. When in proximity, usually only one of these origins fired, suggesting origin interference. Two-dimensional gel analysis of the four origin fragments at their genomic locations demonstrated that each is used in the chromosomes, but in only a subset of cells or cell divisions. The S. pombe genome appears to contain many discrete origins, not all of which fire in any given cell and some of which are closely spaced. Not I/Sfi I mapping of the five origins from this and a previous study indicates that they are randomly distributed throughout the genome and appear to be representative of chromosomal origins of replication in this organism. We compare the features of S. pombe replication origins with those of S. cerevisiae and animal cells.